Allen head screws are widely used by factories, for example, to hold carbide tooling for machining processes where rigidity and reliability of securement are of great importance. These Allen head screws usually have an enlarged circular head formed with a socket therein, the side walls of which are typically hexagonal in cross section to receive an operating rod in the form of a rod which is hexagonal in cross section to snugly fit within the screw socket. The upper end of the operating rod is typically bent at an angle to provide an operating handle. These operating rods or wrenches are unsatisfactory because upon the application of the required torque to tighten, alternatively, loosen the associated screws, may, not infrequently, become bent and break and thereby are rendered useless. This is costly because greater time is required to change the tooling. There is thus a desideratum to provide a tool or driver for an Allen head screw which is not only reliable and efficient, but inexpensive and simple to operate in a variety of locations.
Reference is made to the following U.S. patents which are pertinent only to the chuck construction and not to the spirit or form of the invention: U.S. Pat. No. 709,014 of Sept. 16, 1902 to Jacobs; and U.S. Pat. No. 1,123,541 of Jan. 5, 1915 to Jacobs.